{"id":"CVE-2026-102893","aliases":["EUVD-2026-101287","GHSA-xw9h-9rcm-hx4m"],"status":"published","title":"Zulip: OpenID Connect authentication ignores the email_verified claim","description":"Zulip is an open-source team collaboration tool. In Zulip Server versions through 12.1, GenericOpenIdConnectBackend matches the identity provider email claim to an active account's delivery_email without rejecting an explicitly false email_verified claim. If a configured identity provider returns an email address that the authenticating user does not control together with email_verified=false, Zulip can log the user into the existing account for that address. Exploitation requires a misconfigured trusted identity provider, and deployments whose authoritative identity provider only emits email addresses controlled by the authenticating user are not affected. This issue is fixed in version 12.2.","severity":{"version":"4.0","score":9.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","level":"critical","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.0039,"percentile":0.33516,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-287"],"published":"2026-10-14T15:49:03Z","modified":"2026-10-28T02:30:47Z","products":[{"vendor":"zulip","product":"zulip"}],"references":[{"url":"https://github.com/zulip/zulip/security/advisories/GHSA-xw9h-9rcm-hx4m","tags":["x_refsource_CONFIRM","advisory"]},{"url":"https://github.com/zulip/zulip/pull/39913","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/zulip/zulip/commit/68d2d9defa39f8af96a50fc7430efc34dee120b5","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/zulip/zulip/commit/b40f191a8c71e74fcb471f71de6a1233de157102","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/zulip/zulip/releases/tag/12.2","tags":["x_refsource_MISC","web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/102xxx/CVE-2026-102893.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-102893","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-102893","title":"Zulip: OpenID Connect authentication ignores the email_verified claim","description":"Zulip is an open-source team collaboration tool. In Zulip Server versions through 12.1, GenericOpenIdConnectBackend matches the identity provider email claim to an active account's delivery_email without rejecting an explicitly false email_verified claim. If a configured identity provider returns an email address that the authenticating user does not control together with email_verified=false, Zulip can log the user into the existing account for that address. Exploitation requires a misconfigured trusted identity provider, and deployments whose authoritative identity provider only emits email addresses controlled by the authenticating user are not affected. This issue is fixed in version 12.2.","status":"published","published":"2026-10-14T15:49:03.442Z","modified":"2026-10-15T19:06:20.918Z","cvss":[{"version":"4.0","score":9.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","level":"critical","assessor":"cna"}],"cwes":["CWE-287"],"updated_at":"2026-11-02T13:38:54.394896Z"}],"euvd":[{"id":"EUVD-2026-101287","description":"Zulip is an open-source team collaboration tool. In Zulip Server versions through 12.1, GenericOpenIdConnectBackend matches the identity provider email claim to an active account's delivery_email without rejecting an explicitly false email_verified claim. If a configured identity provider returns an email address that the authenticating user does not control together with email_verified=false, Zulip can log the user into the existing account for that address. Exploitation requires a misconfigured trusted identity provider, and deployments whose authoritative identity provider only emits email addresses controlled by the authenticating user are not affected. This issue is fixed in version 12.2.","status":"published","published":"2026-10-14T15:49:03Z","modified":"2026-10-15T19:06:20Z","cvss":[{"version":"4.0","score":9.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","level":"critical"}],"updated_at":"2026-11-02T17:00:10.766559Z"}],"nvd":[{"id":"CVE-2026-102893","description":"Zulip is an open-source team collaboration tool. In Zulip Server versions through 12.1, GenericOpenIdConnectBackend matches the identity provider email claim to an active account's delivery_email without rejecting an explicitly false email_verified claim. If a configured identity provider returns an email address that the authenticating user does not control together with email_verified=false, Zulip can log the user into the existing account for that address. Exploitation requires a misconfigured trusted identity provider, and deployments whose authoritative identity provider only emits email addresses controlled by the authenticating user are not affected. This issue is fixed in version 12.2.","status":"published","published":"2026-10-14T16:17:29.987Z","modified":"2026-10-16T20:02:37.63Z","cvss":[{"version":"4.0","score":9.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"critical","assessor":"secondary"}],"cwes":["CWE-287"],"updated_at":"2026-11-02T14:12:58.99337Z"}],"osv":[{"id":"CVE-2026-102893","title":"Zulip: OpenID Connect authentication ignores the email_verified claim","description":"Zulip is an open-source team collaboration tool. In Zulip Server versions through 12.1, GenericOpenIdConnectBackend matches the identity provider email claim to an active account's delivery_email without rejecting an explicitly false email_verified claim. If a configured identity provider returns an email address that the authenticating user does not control together with email_verified=false, Zulip can log the user into the existing account for that address. Exploitation requires a misconfigured trusted identity provider, and deployments whose authoritative identity provider only emits email addresses controlled by the authenticating user are not affected. This issue is fixed in version 12.2.","status":"published","published":"2026-10-14T15:49:03.442Z","modified":"2026-10-28T02:30:47.833843943Z","cvss":[{"version":"4.0","score":9.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","level":"critical"}],"cwes":["CWE-287"],"updated_at":"2026-11-02T15:44:53.83521Z"}]}}